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PubMed2005

Aggression, social cognitions, anger and sadness in bullies and victims.

BACKGROUND: The present study aimed to investigate children's social information processing (SIP) and emotions in the bullying situation, taking into account reactive and proactive aggression. More specifically, we investigated the way in which children interpret social information, which goals they select, how they evaluate their responses and which emotions they express in hypothetical situations. METHOD: The participants comprised 242 Dutch children (120 girls and 122 boys; mean age: 117.2 months), who were assigned by means of peer nominations (Salmivalli, Lagerspetz, et al., 1996) to one of the following roles: bully (n=21), follower of the bully (n=38), victim (n=35), defender of the victim (n=48), outsider (n=52) and not involved (n=32). Sixteen children (including 3 bully/victims) were not given any role. The reactive and proactive aggression scale (Dodge, & Coie, 1987) was filled out by teachers in order to test the association between these types of aggression and involvement in bullying. Children were presented with ambiguous scenarios and responded to questions about attribution of intent, goal selection and emotions (anger and sadness). In addition, two questionnaires were administered to children: one assessed perceived self-efficacy in performing aggression, inhibiting aggression and using verbal persuasion skills, and the other assessed expected outcomes from behaving aggressively or prosocially. RESULTS: Results showed that while reactive aggression was common in bullies and victims, proactive aggression was only characteristic of bullies. Both bullies and victims, compared to the other children, scored higher on hostile interpretation, anger, retaliation and ease of aggression. Bullies and followers claimed that it was easy for them to use verbal persuasion, while victims turned out to be the saddest group. All children, irrespective of their role in the peer group, thought that aggressive as well as prosocial behavior was more likely to produce desired results from a friendly peer than from an aggressive one. CONCLUSIONS: Bullies and victims seem to be similar in reactive aggression, SIP, and in the expression of anger, but the motivations which lead to their behavior may be different, as well as the final outcomes of their acts.

Aggression↗
PubMed1995

Gonadal hormones and aggression-maintaining effect of alcohol in male transgenic transforming growth factor-alpha mice.

We have characterized a new transgenic mouse model that offers the unique opportunity to study the biological mechanisms linking aggression to alcohol. In contrast to all other aggressive animal models, the male transgenic mice that overexpress transforming growth factor-alpha (TGF-alpha) maintain their highly elevated aggressive behavior following an alcohol administration. The transgenic mice also exhibit elevated plasma levels of 17 beta-estradiol (E2). Animal data support the role of E2 in aggression and alcohol intake in males. Further, type 2 alcoholism is male-limited, suggesting that gonadal hormones are important. We examined whether gonadal hormones play a role in the resistance to respond to alcohol in the resident-intruder test of aggression among the male transgenic TGF-alpha mice. As previously reported, alcohol had a biphasic effect on sham-operated, nontransgenic controls: 0.6 g/kg increased and 2.0 g/kg inhibited their aggressiveness. Alcohol did not significantly reduce the high levels of aggression in the sham-operated TGF-alpha mice. Castration abolished the difference in aggressive behavior between the transgenic and nontransgenic male mice by reducing aggression. Alcohol did not increase aggressive behavior in these mice. Treatment with pellets releasing 0.25 mg E2 over a 60-day period increased aggression in the castrated male TGF-alpha mice and nontransgenic controls to the levels seen in intact male transgenic mice. Alcohol did not significantly alter aggressive behavior in the E2-treated castrated mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Aggression↗
PubMed1993

Aggressive behaviors among the institutionalized elderly.

OBJECTIVE: To describe the incidence and characteristics of aggressive behaviors in a group of institutionalized elderly. DESIGN: Retrospective survey. SETTING: 350-bed, urban skilled nursing facility. PATIENTS: All nursing home residents who had an incident report completed after an aggressive behavior. MEASUREMENTS: Examination of all incident reports of aggressive behavior for 1 year. RESULTS: There were 94 reports of aggressive behaviors. Twenty-nine residents exhibited one aggressive behavior, 12 residents two, and six residents exhibited three or more aggressive behaviors. These six residents accounted for 44% of all events. The incidence of aggressive behavior was 0.27 per resident per year for the entire facility; on the Alzheimer's unit the incidence was 0.75 per resident per year. Sixty-two percent of the victims of aggressive behavior were other nursing home residents, 37% were employees, and 1% were visitors. The charts of the six residents with three or more aggressive behaviors were reviewed. These residents received trials of multiple scheduled psychotropic medications, often exhibited several additional agitated behaviors around the time of the attack, were at risk for psychiatric hospitalizations during the study period, and often were noted to have underlying acute medical illnesses near the time of the attack. CONCLUSION: Approximately two aggressive behaviors per week occurred in a large nursing home. Residents and staff of Alzheimer's units have a higher risk of being victims of aggressive behavior. A small number of patients account for nearly half of the behaviors, even on the Alzheimer's unit. Aggressive behaviors may be clinical indicators of underlying acute medical illnesses.

Age Factors↗
PubMed2000

Association of aggressive behavior with altered serotonergic function in patients who are not suicidal.

OBJECTIVE: The purpose of this study was to determine whether aggression and serotonergic dysfunction are related in the absence of a history of suicidal behavior. Although serotonergic dysfunction has been implicated in aggressive and impulsive behavior, most studies of such behavior have included individuals with a history of suicide attempts. Low concentrations of CSF 5-hydroxyindoleacetic acid (5-HIAA) have been consistently associated with suicidal behavior, presenting a potential confound in the link between aggression and serotonergic dysfunction. METHOD: The authors examined the association between aggression and CSF 5-HIAA concentrations in a group of 64 patients who had different DSM-III-R axis I diagnoses and no past suicidal behavior. Aggressive (N=35) and nonaggressive (N=29) groups were defined by a median split on a six-item history of adulthood aggressive behavior. RESULTS: The aggressive group had significantly lower CSF 5-HIAA concentrations than the nonaggressive group. Aggressive individuals also scored significantly higher on self-report measures of hostility, impulsiveness, and sensation seeking. CSF 5-HIAA concentrations, however, did not correlate with self-reported hostility and impulsivity. CONCLUSIONS: There is an association between aggressive behavior and serotonergic dysfunction independent of suicidal behavior in patients with axis I disorders who exhibit relatively milder forms of aggressive behavior. Analogous to findings with suicidal behavior, a low concentration of CSF 5-HIAA is related to aggressive behavior but does not show the same relationship to the continuum of aggressive feelings and thoughts.

Adult↗
PubMed2005

An integrated review of indirect, relational, and social aggression.

Over the last decade, researchers have found that girls may be just as aggressive as boys when manipulative forms of aggression, such as gossiping and spreading rumors, are included. These forms of aggression are known by 3 different names: indirect aggression, relational aggression, and social aggression. This review examines their commonalities and differences, and concludes that they are essentially the same form of aggression. We show that analogous forms are not found in other species. We offer a functional account: indirect aggression is an alternative strategy to direct aggression, enacted when the costs of direct aggression are high, and whose aim is to socially exclude, or harm the social status of, a victim. In this light, we consider sex differences and developmental trends and the impact of this aggression on victims. We conclude that indirect, relational, and social aggression are much more similar than they are different, and we suggest ways in which future research can be facilitated by integrating the three areas under an adaptive framework.

Aggression↗
PubMed1989

Aromatase activity in quail brain: correlation with aggressiveness.

Testosterone (T) triggers aggressive behavior in males of many vertebrate species; however, the neural and hormonal basis of individual differences in the frequency or intensity of aggressive behavior is still debated. Using the Japanese quail (Coturnix coturnix japonica), a species in which individuals exhibit a wide range of aggressiveness in nature and the laboratory, together with a newly devised test procedure for quantifying aggressiveness, we recently demonstrated that aggression is estrogen dependent. Here we extend these studies by testing the hypothesis that aromatization in brain is a rate-limiting step in the expression of individual differences in aggressiveness. Using procedures previously validated for this species, aromatase and 5 alpha- and 5 beta-reductase activities were estimated in selected brain regions of reproductively active male quail by measuring conversion of [3H]androstenedione to [3H]estrone, [3H]5 alpha-androstanedione, and [3H]5 beta-androstanedione, respectively. In Exp 1, behaviorally inexperienced test birds were killed 90 sec after a single behavioral test. Aggressiveness of individuals in this group, as determined by pecking and locomotor activity in response to visualization of a conspecific, ranged 3- to 4-fold from high to low. Aromatase activity in the posterior hypothalamus (PHYP) was significantly higher in males rated high for aggressiveness than in animals rated low (1.04 vs. 0.59 pmol/h.mg protein; P less than 0.02). Similar differences were observed in the anterior hypothalamus/preoptic area (AHPOA) but were not significant. In Exp 2, sexually mature males were behaviorally tested eight times over 22 days and killed 24 h after the final test. Aggressiveness varied 5-fold from high to low, although the rating in a given bird remained constant with time and repeat testing. Aromatase activity in the AHPOA was significantly greater in birds rated high for aggressiveness than in low aggressiveness birds (3.77 vs. 2.80 pmol/h.mg protein; P less than 0.02). In addition, when AHPOA aromatase in all birds was plotted against behavioral intensity, there was a 2-fold variation and a significant positive correlation (r = 0.556; P less than 0.02). Similar differences were observed in PHYP, but these were of borderline significance. By contrast, aromatase levels outside the AHPOA and PHYP were unrelated to behavior. Moreover, in both Exp 1 and 2, 5 alpha- and 5 beta-reductase activities in AHPOA, PHYP, and other brain regions; plasma T, 5 alpha-dihydrotestosterone, and total estrogens; and relative testicular weights were not consistently related to aggression.(ABSTRACT TRUNCATED AT 400 WORDS)

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2002

Testosterone, 5 alpha-dihydrotestosterone and cortisol in men with and without alcohol-related aggression.

OBJECTIVE: The present investigation was designed to study steroid hormones, alcohol and aggression interactions in men with a history of alcohol-related aggression (AGG+) and in a cross-sectional control population (AGG-). METHOD: AGG+ (n = 40) and AGG- (n = 44) male volunteers completed the Buss-Perry Aggression Questionnaire and the revised Michigan Alcoholism Screening Test (MAST), after which plasma-free and total testosterone, 5alpha-dihydrotestosterone (DHT) and cortisol were determined. RESULTS: The AGG+ men displayed significantly (p < .05) higher aggression and MAST measures compared with the AGG- men; however, no significant group differences were observed regarding the hormone values. Independently of the steroid hormones, MAST correlated positively with the hostility subscale in both AGG- and AGG+ groups. Free and total testosterone correlated positively with anger and DHT correlated positively with verbal aggression and anger, whereas cortisol correlated negatively with physical aggression and anger in the AGG- group. No significant correlations between steroid hormones and aggression parameters were observed in the AGG+ group. The age factor explained part of the MAST and steroid hormone correlations with aggression. A hormone and MAST independent moderation effect of age upon aggression was also found. CONCLUSIONS: The present study demonstrates an association between alcohol drinking and self-reported sober-state aggression, which implies that the etiology of alcohol misuse and aggressive behavior may involve common biological and/or social factors. These mechanisms, as well as age, androgens and cortisol, all represent factors that, in combination, regulate human aggression.

Adult↗
PubMed1999

Maternal aggression is reduced in neuronal nitric oxide synthase-deficient mice.

Lactating females express rapid extremes in behavior, ranging from gentle nurturance toward offspring to fiercely protective aggression against intruders. Although males often behave aggressively against intruders, female rodents usually express aggression only when rearing and protecting pups. Nitric oxide (NO) inhibits male aggression; however, its role in maternal aggression is unknown. In the present study, female mice with targeted disruption of the neuronal nitric oxide synthase gene (nNOS-/-) displayed significant deficits in maternal aggression relative to wild-type (WT) mice in terms of percentage displaying aggression, the average number of attacks against a male intruder, and the total time spent attacking the male intruder. The nNOS-/- mice displayed normal pup retrieval behavior. Because the specific deficits in maternal aggression in the nNOS-/- mice suggested a possible role for NO in maternal aggression, we combined behavioral testing of WT mice with immunohistochemistry for citrulline, an indirect marker of NO synthesis, to examine indirectly NO synthesis during maternal aggression. A significant increase in the number of citrulline-positive cells was identified in the medial preoptic nucleus, the suprachiasmatic nucleus, and the subparaventricular zone regions of the hypothalamus in aggressive lactating females relative to control mice. In other regions of the brain, no changes in the number of citrulline-positive cells were observed across either groups or treatments. These results provide two indirect lines of evidence that NO release is associated with maternal aggression.

Aggression↗
PubMed2001

Short-term aggressive behavior in scleractinian corals from La Blanquilla reef, Veracruz Reef System.

The short-term aggressive behavior of scleractinian corals from La Blanquilla Reef, Veracruz Reef System, Gulf of Mexico was determined. Unilateral aggression, bilateral aggression and indifference were observed through experimental interspecific encounters in situ, in aquarium conditions and through direct observation of natural encounters on the reef. Species were characterized as highly aggressive, moderately aggressive and not very aggressive establishing a hierarchy with two competitive rings representing similar aggressive abilities among some species. Most observations of aggression were of extracoelenteric digestion. Mussa angulosa was the most aggressive species and Oculina diffusa the least. Apparently there is a direct relationship among aggressiveness and relative coverage as three of the most abundant corals at depths of 4-9 m Montastraea cavernosa, Colpophyllia natans and Montastraea annularis, are all highly aggressive, have massive growth and have a high relative coverage. Siderastrea siderea is the only dominant species that was not ranked as highly aggressive; its high coverage is due to other reasons.

Aggression↗
PubMed2006

[The influence of alcohol use and violent behaviour on the beliefs related to alcohol use and aggression].

The authors examined the effect of personal involvement (drinking, violent behaviour) on beliefs concerning the causal connections between drinking alcohol and aggressive behavior. The sample of the study comprised 1200 persons representative of the population over 18 years of age and was selected by a two-step, group stratified sampling method. The measuring instruments used for the study were the questionnaire on alcohol-aggression beliefs applied by Paglia and Room, the Buss and Perry Aggression Questionnaire, and the sociodemographic characteristics of gender, age and education. Analyses using multivariate regression models showed that aggressive behaviour, particularly verbal and physical aggression, and heavy drinking significantly influence the belief of a causal connection between alcohol and aggression. The more a person drinks and the more aggressive he becomes, the more likely he is not to believe the opinion that drinking leads to aggression. Women and older people have a stronger belief in the causal role played by alcohol in aggressive behaviour. These results draw attention to the importance of the cognitive effect of personal involvement. Heavy drinking and aggressivity can prevent a person from recognizing the danger that drinking can have aggressive, criminal consequences. This relationship can be used well in clinical and criminological practice of crime prevention strategy for patients treated with drinking problems and facing proceedings or condemned for criminal actions. The findings of the study also raise a theoretical consideration that the theory of social learning is not a sufficient explanatory model for the connections between drinking and aggression.

Adult↗
PubMed1996

Patterns of change in early childhood aggressive-disruptive behavior: gender differences in predictions from early coercive and affectionate mother-child interactions.

The present study focused on mother-child interaction predictors of initial levels and change in child aggressive and disruptive behavior at school from kindergarten to third grade. Aggression-disruption was measured via annual reports from teachers and peers. Ordinary least-squares regression was used to identify 8 separate child aggression trajectories, 4 for each gender: high initial levels with increases in aggression, high initial levels with decrease in aggression, low initial levels with increases in aggression, and low initial levels with decreases in aggression. Mother-child interaction measures of coercion and nonaffection collected prior to kindergarten were predictive of initial levels of aggression-disruption in kindergarten in both boys and girls. However, boys and girls differed in how coercion and nonaffection predicted change in aggression-disruption across elementary school years. For boys, high coercion and nonaffection were particularly associated with the high-increasing-aggression trajectory, but for girls, high levels of coercion and nonaffection were associated with the high-decreasing-aggression trajectory. This difference is discussed in the context of Patterson et al.'s coercion training theory, and the need for gender-specific theories of aggressive development is noted.

Affect↗
PubMed1997

Dating aggression among high school students.

Links were examined among physical aggression toward a dating partner, parental aggression, and justification of physical aggression during an argument in a sample of 228 (122 male and 106 female) high school students. Forty-four percent of females and 16% of males reported engaging in at least one physically aggressive behavior toward a dating partner during a disagreement, with the modal form of aggression being push, grab or shove for both males and females. The probability that a male, but not a female, would aggress was significantly predicted by parental aggression and justification of aggression. Among aggressive students, the extent of males' aggression was strongly predicted by their justification of aggression; the extent of females' aggression was not predictable. Implications for prevention and intervention programs are discussed.

Adolescent↗
PubMed1998

Alcohol and heightened aggression in individual mice.

The objective of the current research was to study the large individual differences in alcohol effects on aggressive behavior under systematically varied conditions in experimental protocols with mice. Three experiments were conducted with outbred Swiss-Webster derived mice that identified those individuals whose aggressive behavior was reliably heightened by low acute alcohol doses. In all experimental protocols, low alcohol doses were orally administered to a "resident" male mouse that subsequently confronted an "intruder" opponent for 5 min while all salient elements of aggressive behavior and motor activities were quantified. In all three experiments, alcohol (1.0 g/kg) heightened aggressive behavior by at least two standard deviations of the individual's water vehicle control mean in 27% of the mice. In 64% of mice, no reliable change in aggressive behavior was detected after the identical alcohol treatment, and in 9% of the mice alcohol decreased aggressive behavior. Experiments differed in protocol indicating that these aggression-heightening effects were evident in resident mice that were either maintained at restricted or unlimited amounts of food, housed singly or in breeding pairs with a female partner, and conditioned to perform daily a food-reinforced task or remained undisturbed. The first experiment found the aggression-heightening effects to persist during weekly challenges for at least 2 months (n = 8 of 30). The second experiment showed these effects at intervals from 5 to 60 min after alcohol administration. Blood alcohol concentrations reached peak level within 5 to 10 min after oral administration in mice that had confronted an intruder. Those mice in whom alcohol heightened aggressive behavior (n = 21) did not differ from those that showed suppressed levels (n = 9) in terms of blood alcohol concentrations (79.6 vs. 82.4 mg%), suggesting that the intensity and frequency of aggressive behavior after alcohol were not directly dependent on the amount of alcohol in the circulation. The third experiment revealed that alcohol's (0.1 to 5.6 g/kg) effects on heightened aggressive behavior (n = 11) are dissociated from those on concurrently measured high- or low-rate operant performance as engendered by a multiple FR 30-FI 600 sec schedule of reinforcement. Current results indicate that this alcohol effect is relatively specific to aggressive behavior in individual animals, offering the opportunity for neuropharmacological and molecular characterization.

Aggression↗
PubMed2026

Genomic characterization of aggressiveness in pituitary neuroendocrine tumors.

BACKGROUND: Aggressive evolution of PitNETs is rare; metastatic spread is even more. Defining aggressiveness and malignancy is challenging, subsequently hard to predict, and to understand. The aim was to provide a molecular definition of aggressiveness using genomic approaches. METHODS: PitNETs from 206 patients were included. Associations between 9 clinicopathological features of aggressiveness and PitNETs' omics were explored. Omics included transcriptome, DNA methylation, chromosomal alterations, and mutations. Clonal tumor evolution was monitored in 7 patients. RESULTS: Among the 9 clinicopathological features of aggressiveness, only rapid progression, progression after radiotherapy, Ki67/MIB1 proliferation index &#x2265;10%, temozolomide treatment, metastases, and specific death were associated with specific omics signatures, while tumour maximal diameter &#x2265;40 mm, cavernous, and sphenoid invasion were not. The omic signatures associated with these features of aggressiveness overlapped but remained distinct between corticotroph and mammo-somato-thyrotroph lineages. For each lineage, a common signature of aggressiveness was identified, associating a proliferative transcriptome signature and DNA hypermethylation. Alterations in specific genes were associated with aggressive features, including a novel PitNET gene, LRP1B, and known cancer genes (TP53, CDKN2A), while USP8 and GNAS alterations were not. Integration of gene alterations with methylome and transcriptome signatures isolated a subset of molecularly aggressive PitNETs. Molecular signatures were stable during the course of the disease, despite evolution toward aggressiveness and potential clonal divergence. CONCLUSION: This systematic analysis of clinicopathological features of aggressiveness using an integrated multiomic approach establishes a histomolecular definition of aggressiveness in PitNETs. Prospective cohort studies are needed to validate these molecular signatures and establish their prognostic value.

Humans↗
PubMed2006

Potentially modifiable resident characteristics that are associated with physical or verbal aggression among nursing home residents with dementia.

BACKGROUND: Physical aggression by nursing home residents is a burden to residents and staff. The identification of modifiable correlates would facilitate developing preventive strategies. The objectives of the study were to determine potentially modifiable resident characteristics that are associated with physical aggression and to correlate these characteristics with verbal aggression. METHODS: This was a cross-sectional study of nursing home residents in 5 states who had at least 1 annual Minimum Data Set assessment completed during 2002. Case subjects were defined as nursing home residents 60 years and older with dementia who were reported to have been physically aggressive in the week before their assessment. Control subjects were all other residents 60 years and older with dementia. The main outcome measure was being physically aggressive during the past week. RESULTS: A total of 103 344 residents met study criteria, of whom 7120 (6.9%) had been physically aggressive in the week before their annual Minimum Data Set assessment. After adjustment for potential confounders, including age, sex, severity of cognitive impairment, and dependence in activities of daily living, physical aggression was associated with depressive symptoms (adjusted odds ratio [AOR], 3.3; 99% confidence interval [CI], 3.0-3.6), delusions (AOR, 2.0; 99% CI, 1.7-2.4), hallucinations (AOR, 1.4; 99% CI, 1.1-1.8), and constipation (AOR, 1.3; 99% CI, 1.2-1.5). Urinary tract infections, respiratory tract infections, fevers, reported pain, and participation in recreational activities were not significantly associated with physical aggression in multivariate analyses (P >.01 for all). Except for constipation, the correlates of verbal aggression were similar to those of physical aggression. CONCLUSION: If the associations we have estimated are causal, then treatment of depression, delusions, hallucinations, and constipation may reduce physical aggression among nursing home residents.

Aged, 80 and over↗
PubMed1998

Cerebrospinal fluid vasopressin levels: correlates with aggression and serotonin function in personality-disordered subjects.

BACKGROUND: Animal studies suggest that central vasopressin plays a facilitatory role in aggressive behavior. To examine this possibility in humans, the relationship between cerebrospinal fluid (CSF) arginine vasopressin (AVP) and indices of aggression and central serotonin system function was examined in personality-disordered subjects. METHODS: We used CSF (AVP), CSF 5-hydroxyindoleacetic acid, and the prolactin response to d-fenfluramine challenge (PRL[d-FEN]) as central indices of vasopressin and serotonergic system function, respectively, in 26 subjects who met the DSM-IV criteria for personality disorder. Measures of aggression and impulsivity included the Life History of Aggression assessment and the Barratt Impulsiveness Scales. RESULTS: The CSF AVP level was correlated directly with life history of general aggression and aggression against persons and inversely with PRL[d-FEN] responses (but not with CSF 5-hydroxyindoleacetic acid), which in turn was correlated inversely with these 2 measures of life history of aggression. The positive relationship between CSF AVP and life history of aggression remained even when the variance associated with PRL[d-FEN] responses in these subjects was accounted for. CONCLUSION: Central AVP may play a role in enhancing, while serotonin plays a role in inhibiting, aggressive behavior in personality-disordered individuals. In addition to the possibility of central AVP and serotonin interacting to influence human aggression, central AVP may also influence human aggressive behavior through a mechanism independent of central serotonin in personality-disordered subjects.

Adult↗
PubMed1998

Fearlessness, stimulation-seeking, and large body size at age 3 years as early predispositions to childhood aggression at age 11 years.

BACKGROUND: Previous cross-sectional research in Western societies has linked adolescent stimulation-seeking, fearlessness, and body size to antisocial behavior. However, it is unclear how early in life these factors exert their influence, and nothing is known about their specificity to aggressive behavior per se. This study tests the hypotheses that stimulation-seeking, fearlessness, and increased body size at age 3 years predict aggression at age 11 years. METHODS: Behavioral measures of stimulation-seeking and fearlessness, together with height and weight, were measured at age 3 years and related to ratings of aggression at age 11 years in 1130 male and female Indian and Creole children from the island of Mauritius. RESULTS: Aggressive children at age 11 years were characterized by increased measures of stimulation-seeking, fearlessness, height, and weight at age 3 years. Stimulation-seeking and height were independently related to aggression, whereas the fearlessness-aggression relationship was mediated by height. Large body size at age 3 years but not 11 years was related to increased aggression at age 11 years, indicating a critical period in development for the influence of body size on aggression. CONCLUSIONS: Results (1) implicate large body size, stimulation-seeking, and fearlessness in the development of childhood aggression; (2) suggest that there may be a critical period in development in which biological processes influence later aggression; and (3) highlight the importance of early processes in the etiology of aggression.

Age Factors↗
PubMed2000

Low salivary cortisol and persistent aggression in boys referred for disruptive behavior.

BACKGROUND: Persistent antisocial behavior in adulthood is often preceded by childhood-onset aggressive conduct disorder. Aggressive syndromes in both children and adults have previously been associated with abnormalities in peripheral responses to stress. One peripheral measure, salivary cortisol concentration, may reflect individual differences in the hypothalamic-pituitary-adrenal axis that underlie propensities for aggression, socialization, and adaptation to stress. METHODS: The relationship between salivary cortisol levels and aggression was tested in 38 clinic-referred school-aged boys. Persistent aggression was measured by collecting disruptive behavior disorder symptoms in 4 annual clinical evaluations and peer nominations of aggression in the first 2 annual evaluations. Salivary cortisol levels were measured during years 2 and 4 of the study. RESULTS: Low cortisol levels were associated with persistence and early onset of aggression, particularly when measures of cortisol concentrations were pooled. Boys with low cortisol concentrations at both time points exhibited triple the number of aggressive symptoms and were named as most aggressive by peers 3 times as often as boys who had higher cortisol concentrations at either sampling time. CONCLUSIONS: This suggests that low hypothalamic-pituitary-adrenal axis activity is a correlate of severe and persistent aggression in male children and adolescents. A restricted (low) range of cortisol variability may be more indicative of persistent aggression than a low concentration of cortisol at any single point in time.

Adult↗